how do I accomplish these two? I just can't seem to get it right... What I want to do is to just allow myself access to the site and redirect everyone else to the construction page (my site is under construction)

Well it finally works now but now I have another question, it's concerning the redirect from earlier, i found out why I had such trouble from it, because I was testing it on another computer from within my house, and once I tried it on a proxy site, the redirect worked, I then realized that all of the computers in my house share the same public IP but just different LAN IPs, but I tried using my LAN IP in the .htaccess file, and it redirected me (which is not what I want), so how can I redirect all the computers in the house and everybody else in the world? (though I already accomplished the everybody in the world part lol)

Ah okay. Yes, you can't do that. Have you considered installing a web server on your own PC for development purposes? That's also nicer because it's all local and thus faster and you don't have to upload files all the time

Although I'm a day late and a dollar short, the way I do it is to use DirectoryIndex public_link private_link so that the public only see the public link (index.html) while I link directly to the private_link (index.php). That way, I can have visitors see the "under construction" notice while I can see (and provide links for my clients) the "work in progress."